Disappearing stairway



Patentedl Jan. 29,1946

UNITED 4's'rli'iisis PATENT o Fries Dlssrrnaamc s'rslawn Willard n;pekin, Akron, ome Appiiestien september 14', 194s, serial No. stamc-cisims. ici.. zza-soi 'rms invention relates to disappearing steir-Wy.

Its chief objects are:

To provide simplicity, economy anddurability;

To provide a stairway and associated mechanism adapted to be storedwholly within the and from use position fromeither the upper floor orthe lower floor;

To provide a trap-door balancing each other that they can be moved toand from use position with little eifort, and to provide an "over-centereilect so that the assembly will be rmly held in use position by lllvltyand will be rmly held in Stored P051- tion by gravity:

To avoid the use of vcable-and-pulley devices and of springs forcounteracting the weight of the stair. and thus to eliminate'their tagesof wear'. breakage and danger;

To provide numerousand widely spaced points of support for the stairwhen in use and when vbeing moved to and froml stored position;

To provide automatically presented and automatically stored hand rails;

To provide other advantages which arev in'- I heren't in the structureherein described.

Of the accompanying drawings:

and stair so counter- I The track-ways I1 are the same incross-sectional form as track-ways, such as that shown at I8, which aresecured by screws I9, I9 (Fig. 3)

to the outer faces' of the side members of the 'l stair, and the rollersI6 are of the same construction as the rollers that are adapted to runin the track-ways I8, one. or which rollers is shown at' ,20 (see Fig.3).

Secured to each of the joists, I2, by screws 2|,

2|, is a face plate 22 formed with two holes in which respectively areriveted a large, shouldered axle-stud 23 and a smallenvshoulderedaxle-stud 24, projecting toward the middle of the stair well.

Each of the studs 24 is connected with a stud 25 projecting 'from theadjacent side of the stair by a thin, flat link member 28, which isadapted to act as one arm of a toggle, of which the other arm is theupper portion of the stair, for shifting the upper end of the stair tothe right, along disadvanthe guide-ways I'I, when the stair is swungupward about the moving axis I8. Thus the upper end of the stair movesto the position a as its lower end moves to the position b.

This shifting-axis feature permits the useof a stair almost as long asthe ceiling joists, so that -it is not excessively steep when in use,and4 at the same time provides upper and lower landings of adequatesize.

An opening 2'I in the oor of the upper room is adapted to .be closed bya trap-doorn which is hinged at 28. The trap-door preferably but notnecessarily consists ofiiloorins boards I3, I, held together preferablyby a sheet-metalv plate n secured te their under faces by screws such asthe screw 3| (Fig. 4) along the side marginsof themetal plate; near theends of the Fis. 1 is a vertical middle section of a stair andassociated structure embodying my invention in its preferred form. i

Fig. 2 is a section, on a larger scale,on the indirect line 2--2 ofFig.1.

Fig. 3 is a section on linel--i of Fig.` 1.

-4 is a section on line l--I of Fig. i. Referring to the drawings, themechanism; is shown installed lin a `room of which thezstuddins .isshown at I0, i.: the plates at II,'.II. one of the joists at I2, boardsof the upper floor at I3, Il, and the floor ofthe lower room at I4.

The stair, I. is provided on'each side of its upper end with anoutwardly projecting axleboards I3, sothat the metal plate serves as abridge member to.v give the door great strength for supporting weightwhether or not the plate litself directly engages the joists.lPermissibly it can come to'rest upon the .upper edges o f'the axle-studplates 22 (compare Figs. 4 and il).

Secured to the lower face of the plate Il are a pair of guide-ways ofwhich one is shown at I2 for guidingvresp'ective rollers such .astheroller 33; which can be of the same size'andA construction as/ thetwo other pairs of rollers II' and 20.-

and-roller, assembly Il,l the rollers being of horiliontallyv inrespective track-ways, such as the one shown atI'I. secured to therespective joists' at the two sides o! the -grooved or waisted form andadapted to run.

For economy each or lthe six rollers vcan be formed or three sheet-metaldiscs spot-welded together. providingsuch mechanical' connection between the stair lIl and the trap-door 2l4 that they will counter-balanceeach other, with the "overy center enect above referred to inthestatement 'oi objects, the rollers are mounted respectively ,uptm the`upper ends. and the rollers."

mounted respectively upon the lower ends, of a pair of actuating leversof which one is shown at 34, said levers being fulcrumed respectivelyupon the axle-studs 23.

When the trap-door 28 and its metal reinforcing plate 30 are oisufiicient size and weight they can alone serve as a suiiicientcounter-weight for the stair, but if the proportions and weights ofparts are not such as to provide adequate counter-weight without more aspecial counter-weight 35, adapted to be received between steps of thestair, can be secured to'the under face of the door.

lThe structure thus far described provides a simple, dependable, safeand durable mechanism for installations where hand-rails paralleling thestair are not required, the nearly vertical actuating levers 3d and theangularly disposedlinks- 2E serving well as hand-holds,

Such construction is well adapted, however, for combinationvwith a pairof 'hand-rails, such as the one shown at 36, hinged respectively uponthe axle-studs 2d and at a lower position connected with the stair byparallel-motion links such as the link 3l having the same effectivelength, between pivots, as the toggle-links 2t.

Bracket-like clips such as those shown at @t andv 39 can bemounted onthe link @l and handrail 36 respectively and adapted to receive theactuating lever 3H as the stair comes to use position, for giving thehand-rail additional points of support against lateral displacement.

The mechanism can be operated either from the upper iloor, by manualengagement ofthe f trap-door, which preferably is provided with anin-set handle ring 40, or from the lower floor, by manualengagement of apull cord die attached to the stair. Only a small force is required formoving the assembly from the dotted-line stored position to thefull-line use position, or back to the .stored position. The storedposition of the actuating lever 34 is shown at c and that of thehand-rail 38 at d.

A panel 4l of ceiling material or of ply-wood can be secured to theunder side of the stair. so that when the stair is in stored positionthe opening in the ceiling will be closed by it. It also serves thepurpose of risers, which is of some importance in View of the fact thatsome persons dislike to use stairs thatv they can see through.

Preferably a bar l2 of triangular cross-section is secured to the lowerend of the stair and, like the panel, projects to the middle plane ofthe joist at each side, to serve as a; large-area foot for the stair andas a stop for the stair in its stored position, the projecting endportions of the foot abutting the under edge faces of the ioists.

It is clear from an inspection of Figs. 2, 3 and 4 that only a verynarrow space is required for the mechanism at each side ot the stair,'especially when the strip members are o! sheet metal, and that they canbe of such thickness as to be 'made of wood without very much increaseof the width ot those spaces. l l

The parts areiirmly held in use position by gravity because when theyare in that position the weight of the door assembly is sustained'largely by its hinges 29, with only a small torque force sustained bythe actuating levers Il, and

by gravity because when they are in that position .the actuating bars 34sustain a greater part of the weight oi the door assembly, with onlyabout half of the weight'ot the stair sustained by the bars at theirother ends, and with no mechanical advantage for either-other than thedifference in the lengths of the lever arms, which isv not a Thisover-center eiiect can be had throughout a wide range of relativedimensions and relative weights of parts, without changing the leverageposition or size oi.' the counterweight. Correspondingly, the assemblydoes not involve any difilcult balancing problem.

A longer range of movement of the upper end of the stair can be providedby using` a shorter stair or increasing the length oi the toggle arms.or by doing both. The structure is such that the device can be operatedfrom either the upper iioor or the lower :door even when the parts areso proportioned that the angle between the-links 26 and the upper endportion of the st'air is substantially less than a right-angle.

Various modifications are possible without sacriiice of all of theadvantages set forth in the above statement of objects and withoutdeparture from the scope of the appended claims.

I claim:

l. The combination of a'stair having movingpivot mounting means at itsupper end, a link having a iixed axis at one end and pivoted to thestair at its oth'er end, a hand rail pivoted on the said fixed axis, andasecond link connecting the hand-rail with the stair, the hand-rail, thetwo links and the stair constituting a parallel-motion.

2. A stairway assembly comprising a pair of horizontally disposed,spaced-apart, side members, a door supported by' said members and havinga stair-opening between them, runway means disposed at leastapproximately lengthwise of, and on the inner face of, said members, astair,

runner means on the upper end portion of the stair for coaction withsaid runway means, and

a link having one of its axes xed with relation to one of said sidemembers and its other axis vfixed with relation to the stair.

3. A stairway assembly comprising a door structure having astair-opening therein, at least approximately horizontal runway meansmounted in xed relation to and below the upper face of said. iioorstructure, a full-length, rigid stair,-

runner means on the upper end portionvoi the stair for coaction withsaid runway means, the runway means and the runner means constituting amoving-pivot connection about which the stair l can beswung upward tostored position and downvin an atleast approximately horizontalposition,

the assembly including a hand-rail and means so connecting it to the-iioor structure and 'to the stair as to cause it to lie close to andatleast approximately parallel to the stair when the latter alsobecausevth'e weight of the stair has a substantial mechanical advantagebyv reason of the angular relation of the guide rails il and the leversIl..

'I'he parts are strongly held in stored position is in stored positionand to be brought to useposition by swinging of the stair to useposition.

` 4. A stairway assembly comprising a tloor struc-l j ture having astain-opening therein, at least approximately horizontal runwaymeansmounted in ilxed relation to and below the upper face ot n said doorstructure. a fun-length. rigid stair,

runner means on the upper end portion of the stair for coactlon withsaid runway means, the runway means andthe runner,` means constituting amoving-pivot connection about which the stair can be swung upward tostored position and downward to use position, and means for stopping thestair in use position, the dimensions and positions oi.' the recitedelements being such that when in use position and also when in storedposition the stair iswholly below the upper face of said iioor structureand wholly within its horizontal limits and, when in stored position, iswholly disposed in an at least approximately horizontal position, thecombination including a, trap-door hinged to the floor structure forclosing the stair opening, runway means on the trap-door, runway meanson the stair, a lever fulcrumed on an axis fixed with relation to thefloor structure, and runner means on respective arms o! the lever forcoasting with the last mentioned two runway means respectively.

5. A stairway assembly comprising a floor strucvture having astair-opening therein, at least approximately horizontal runway meansmounted in fixed relation to and below the upper face of said floorstructure, a "full-length rigid stair, runner means on the upper endportion of the ward to use position, and means for stopping the' stairin use position, the dimensions and positions of the recited elementsbeing such that when in use position and also when in stored positionthe stair isv wholly below the upper face of said iloor structure andwholly within Aits horizontal limits and, when in stored position, iswholly disposed in an at least approximately horizontal position, thecombination including a trap-door hinged to the floor structure forlclosing the stair opening, and means so connecting the stair and thetrapdoor that movement of one of them toward vertical position andtoward horizontalV position effects corresponding movement of the other.

6. A ladder assembly comprising a supporting structure having at leastapproximately horizontal runway means thereon, a ladder having at oneend runner means hingedly associated with said runway means, and a linkhaving one of its axes xed with relation to said supporting structureand its other axis iixed with relation to the ladder,

WIILARD D. EAKIN.

